Breast-drill



K. DROZD.' BREAST DRILL."

- I APPLICATION-FILED use. 22. 1919. v 17,350,144. Patented Aug. 17, 1920.

2 SHEETS-SHEET I.

JLT ll r oztt- K. DROZD.

BREAST DRILL- APPLICATION man nzc.-22, 1919.

Patent ed'Aug. .17, 1920.

2 SHEETSS.HEF T 2.

UNITED STATES PATENT GFF'IQE.

KAZIMIERZ DROZD, F 'WILLOCK, PENNSYLVANIA.

BREAST-DRILL.

Specification of Letters Patent. Patented Aug. 17, 1920.

Application filed December 22,- 1919. Serial No. 346,738.

To all whom it may concern:

Be it known that I, KAzIMIERz DRozn, a citizen of Poland, residing at Willock, in the county of Allegheny and 'State of Penn: sylvania, have invented certain new and useful Improvements in Breast-Drills, of which the following is a specification.

a The present invention has particular reference to a breast drill of-a type that is capable of adjustment to permit an interchange of meshing gears for varying the speed of operation with the employment of a constant source of power.

' drill illustratin A further objectof the invention is to provide a breast drill of the type wherein the operator is adapted to bear against the frame of the drill forfeeding the drill into an object to be forced with manually operated devices for rotating the drill.

' With the above general objects in view and others that, will become apparent as the nature of the inventionis better understood, the same consists in the novel combination and arrangement of parts hereinafter more fully described in connection with the accompanying drawings, and wherein like reference characters designate corresponding parts throughout the several views,

Figure 1 is a front elevational view of a breast drill constructed in accordance with the present invention,

Fig. 2 is a side elevational view thereof,

Fig. 3 is a front elevational view of the the gears as being shifted with respect to ig. 1 by changing the speed of rotation of the drill,

Fig. 4 is an enlar ed cross sectional view taken on line IVI of Fig. 3 showing the shifting gears locked in one position, and

5 is an enlar ed cross sectional view taken on line V of Fig. 1 showing the adjusting screw for longitudinally shifting the speed changing gears.

Referring more in detail to the accomanying drawings, there is illustrated a reast drill embodying a frame formed of side bars 6 having inwardly tapered portions 6 at their outer ends that are connected by a cross head, the inner ends of the side bars being riveted, or otherwise secured to the flat breast bar 8 having angularly bent ends 8' for holding the breast bar positioned relative to the body. As shown in Figs. 1 and 3, a cross brace 9 extends between the side bars 6 at their points of connection with the tapered portion 6' and coiiperating with the breast bar 8 for maintaining the bars 6 in parallelism.

A drill shaft 10 is journaled longitudinally of the frame in the cross head 7 and brace 9 and has fixed thereto at opposite sides of said cross head 7, collars 11 to prevent longitudinal movement of the shaft while the inner end of the shaft 10 spaced inwardly of the brace 9 carries a cylinder 12 fixed thereto as indicated'in Figs. 1 and 3 and being provided upon the extreme inner end thereof with a beveled gear 13. A double socket member 14 is carried by the outer end of the shaft 10 and detachably supports a drill 15 of any preferred type.

The driving mechanism for the drill includes like devices associated witheach side bar 6, each device embodying spaced angle brackets 16 carried by the inner and outer sides of the side member 6 with a rotatable portion 18 in the side bar 6. A screw 19 longitudinally disposed within said cutaway portion 18 has its lower end keyed to said rotatable block by the pins 20 whereby said screw is rotated within said cutaway portion 18 upon rotation of the block 17 without changing its position relative to the side bar. A bearing pl te 21 is associated with each side bar 6 and is-disposed inwardly of the side bar in contact therewith, the bearing plates carrying depending hanger blocks 22 disposed within the cutaway portions 18 and having threaded openings therein for the reception of the screws 19. A transverse power shaft 23 is journaled transversely of the side bars 6 in the bearing plates21 While rectangular plates 24 upon the shaft 23 exteriorly of the side bars 6 are secured to the bearing plates 21. by the screws 25 to hold the bearing plates substantially rigid with the side bars. Collars 26 are fixed to the shaft 23 at points outwardly of the plates 24 to prevent a longitudinal movement of the power shaft 23. As illustrated in Figs. 1 and 4, the ends of the power shaft 23 carry key projections 27 for the reception of crank handles 28 rotating said shaft. Means is provided for communicating motion from the power shaft 23 to the shaft 10 and embodies a sleeve bearing 29 slidable on said power shaft 23 and maintained in adjusted positions by transverse pins 30 passing large bevel gears 32 and 33 are formed integral with the sleeve 29 and are adapted for meshing engagement with the bevel gear 13 upon the drill shaft 10.

As illustrated in Fig. 1, the gear 13 is in mesh with the large gear 33 and with the operation of the crankhandles 28, the power shaft 23 is rotated, and motion communicated from the gear 33 to the gear 13 for the rotation of the drill shaft 10 and drill 15. When it is desired to reduce the speed of rotation of the drill 15 with a constant supply of power to the shaft 23, the pins 30 are removed from the sleeve 29 to permit a sliding movement of the sleeve over the power shaft whereby the pin receiving openings in the sleeve will register with the other set of .openingsin the power shaft with a subsequent locking of the sleeve to the power shaft by the insertion of the pins in the registering openings. With this change of position of the gears, the blocks 17 are rotated and by the'screw connection 18 with the block hangers 22, the bearing plates 21 are shifted longitudinally of the side bars 6 to move the small bevel gear 32 to meshing contact with the gear 13. It will therefore be seen that with a lateral shifting of the gear carrying sleeve 29, andwith a longitudinal shifting of the bearing plates 21, gears 32 and 33 are caused to selectively engage the gear 13 to vary the speed of rotation of the drill 15 with a constant supply of power to the shaft 23.

While there is herein shown and described the preferred embodiment of the invention, it is nevertheless to be understood that minor changes may be made therein as will fall within the spirit and scope of the same.

What is claimed as new is: 1. A breast drill comprising a frame, a

drill shaft journaled longitudinally thereof, a power shaft journaled transversely of said frame, a gear fixed to the inner end of the drill shaft, a sleeve adjustably fixed to the power shaft, relatively large and small gears carried by said sleeve and movable with the sleeve over the power shaft to aline either of the large or small gears with the power shaft gear, means for shifting the power shaft longitudinally of the frame to move either of said gears into meshing contact with the gear upon said power shaft, said last named means comprising a pair of screws journaled in the frame and connections between said power shaft and screws.

2. A breast drill comprising a frame, a drill shaft journaled longitudinally thereof, a power shaft journaled transversely of said frame, a gear fixed to the inner end of the drill shaft, a sleeve adjustably fixed to the power shaft, relatively large and small gears carried by said sleeve and movable with the sleeve over the power shaft to aline either of the large or small gears with the power shaft gear, means for shifting the power shaft longitudinally of the frame to move either of said gears into meshing contact with the gear upon said power shaft, said last named connections including bearing plates for said power shaft, block hangers carried. by said bearing plates, adjusting screws movable relative to said frame and cooperating with said block hangers to shift the bearing plates and power shaft with the gears supported thereon.

In testimony whereof I affix my signature in presence of two witnesses.

KAZHHER-Z DROZD.

Witnesses NANNIE MoKE-E, ISABEL BRANKS. 

